Patent – EF 135 f/2.8 & 180 f/3.5 with Apodization Filter

New lens patents
A new patent showing two lenses, the 135 f/2.8 and 180 f/3.5 has appeared. The interesting part of these patents is something called a apodization filter on the lenses. This improves the bokeh performance of the lenses.

Could either of these lens patents translate into a new 135 f/2L or 180 f/3.5L Macro? Only time will tell.

Read more after the break…

Patent Publication No. 2012-128151

• 2012.7.5 Release Date
• 2010.12.15 filing date

Example 1

• 137.2mm – f = 135.0 focal length
• Fno 2.83 -. 3.90
• 9.1 deg half each painting.
• Image height 21.60mm
• 186.7mm – 150.0 full-length lens
• BF 47.4 – 80.7mm
• Lens Construction 10 elements in 7 groups sheet
• 1 UD glass sheet
• 0.25 times the maximum magnification ratio

Example 6

• 179.1mm – f = 180.0 focal length
• Fno 3.50 -. 4.00
• 6.9 deg half each painting.
• Image height 21.60mm
• 218.0mm – 199.8 full-length lens
• BF 70.0 – 89.8mm
• Lens Construction 11 elements in 7 groups sheet
• 1 UD glass sheet
• 0.11 times the maximum magnification ratio

Appearance of (Bokeh) is important out of focus

Apodization filter

• The periphery of the filter transmittance is reduced
• Added to the luminous flux intensity distribution
• Bokeh is beautiful and the outline of the

Apodization element variable

• If the liquid of same refractive index as the shape of the interface, no variation occurs in aberration
• To be the same refractive power of the two liquids, the Abbe number is difficult

Canon ‘s patented

• Variable element shape
• Voltage is applied, changing the shape of the interface
• Obtain the effect of apodization
• Varying refractive power, the Abbe number
• To reduce the time variable aberrations of shape
• By a twist of the material performed, to optimize the absorption coefficient, to suppress the generation of aberration to moderate the curvature of the interface
• To reverse the two materials (such as liquid), the amount of chromatic aberration, do the negation
• Suppress the two materials (such as liquid), refractive index, the difference between the Abbe number
• The entire feeding (with floating)